A pharmaceutical preparation containing three kinds of branched chain amino acids of isoleucine, leucine and valine as active ingredients is an effective therapeutic agent for liver diseases. These three kinds of branched chain amino acids have a strong bitter taste and unique amino acid smell and require large amounts for one dose. For production of a preparation, therefore, the problems of reduction of bitter taste and smell, a small-volume of a dose and the like should be solved.
In particular, when a solid preparation contains particles of these three kinds of branched chain amino acids, the preparation is required to have uniform contents of these three kinds of branched chain amino acids per dose. However, when this requirement is to be met by reducing the size of starting material amino acid particles as in the case of conventional solid preparations, the volume thereof in one dose increases, which in turn makes the preparation bulky and difficult to swallow during administration.
In the case of granules, for example, the active ingredient is mostly pulverized to not more than 50 μm before use, thereby to satisfy the requirements of ensured content uniformity, improvement in solubility and the like. The granules produced in this way generally show a specific volume of 2.0 mL/g or above, though subject to slight change depending on the type of granulation method, granulation conditions and the like. In the case of the aforementioned three kinds of branched chain amino acid particles, a single dose of the branched chain amino acids is about 4–5 g. Therefore, when a granule preparation is produced by pulverizing them to not more than 50 μm, its volume becomes about 8–10 mL and takes up much space in the mouth, making it extremely difficult to swallow.